Crush the chillies and ginger together with a pinch of salt with a pestle and mortar (or blender) to make a fine marsala paste.
Heat the oil in a large thick-based frying pan over a medium heat for 30 seconds before adding the cumin and mustard seeds.
When the mustard seeds start to pop, reduce to a low heat and stir in the asafoetida (heating the spices in this order is essential to the flavour of the dish).
Use a wooden or heatproof plastic spoon to stir in the cauliflower, return the heat to medium, then stir in the marsala paste, turmeric, ground coriander, salt, sugar, and boiling water (if using fresh peas).
Cover the pan and leave to cook for 8-10 minutes, stirring every few minutes.
Stir in the peas and tomato, re-cover and cook for a further 3-5 minutes before removing from the heat.
Sprinkle with the chopped coriander, re-cover and leave to rest for 5 minutes to let the flavours develop.
Recipe courtesy of ‘From Bombay to Britain’, the official National Curry Week Recipe Book